Debt instrument, third party credit issuance, amount.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Fair value of trust owned, percentage.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The aggregate amount of the participation liability at the end of the accounting period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 30
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=99377297&loc=d3e10013-112621

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of new stock issued during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Paragraph 1
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+ Details

Name:	us-gaap_StockIssuedDuringPeriodSharesNewIssues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
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Balance Type:
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- Details

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- Details

Name:	srt_OwnershipAxis=ston_PaylessHoldingsLLCMember
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Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=ston_AxarMember
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Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_TypeOfArrangementAxis=ston_CommonStockPurchaseAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=srt_BoardOfDirectorsChairmanMember
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RELATED PARTIES - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended	9 Months Ended
	Jun. 30, 2020	Sep. 30, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Debt amount issued by third party entity			$ 70
Stone Mor Inc
Related Party Transaction [Line Items]
Participation amount in debt issuance			30
Axar
Related Party Transaction [Line Items]
Participation amount in debt issuance			$ 20
Payless Holdings LLC \| Stone Mor Inc
Related Party Transaction [Line Items]
Percentage of fair value trust owned		4.00%	4.00%
Axar
Related Party Transaction [Line Items]
Ownership interest of Partnership's outstanding common units		61.80%
Axar \| Common Stock Purchase Agreement
Related Party Transaction [Line Items]
Issuance of Series A Preferred Stock\units (in shares\units)	23,287,672
Mr. Axelrod, Chairman \| Payless Holdings LLC \| Axar
Related Party Transaction [Line Items]
Equity owned percentage			30.00%